Regulatory systems
What is the purpose of repressor and activator proteins?
Repressor=turns off expression
Activator=turns on transcription
What is the name of the cleavage between two cells right before cell division is complete?
Septum
What are antibiotics?
Antimicrobial substances naturally produced by microorganisms
What is a mutation?
Heritable change in nucleotide sequence of DNA
What is horizontal gene transfer?
Movement of genetic material between organisms other than by descent
What are the two proteins involved in a two-component regulatory system?
Sensor kinase and response regulator
Endospore formation is triggered by what type of conditions?
Adverse conditions (ex. starvation , desiccation, inhibitory temperatures)
What antibiotic class inhibits transpeptidation in cell wall synthesis?
B-lactams (ex. penicillin)
What type of mutation changes a single base pair but does not alter the amino acid sequence?
Silent mutation
Which process involves uptake of free DNA from the environment by a bacterial cell?
Transformation
Which signaling molecule allows bacteria to coordinate quorum sensing?
Autoinducer
What protein forms the ring at the center of a bacterial cell during binary fission?
FtsZ
Which antibiotics inhibit RNA synthesis by binding to RNA polymerase?
Rifampin and actinomycin
What type of mutation results from the insertion or deletion of bases that shifts the reading frame?
Frameshift mutation
What is the name of the small, circular DNA molecules that often carry antibiotic resistance genes?
Plasmids
What is the alternative sigma factor that directs transcription of heat shock response genes in E. coli?
RpoH (sigma^H)
What system makes sure that each daughter cell receives one copy of chromosome during division?
Par (partitioning) system
What is the meaning of persistence?
Population of antibiotic-sensitive bacteria that are transiently tolerant to multiple antibiotics.
What is the term for a mutation that restores the original phenotype by compensating for another mutation?
Suppressor mutation
Which mobile genetic element can move from one DNA site to another, sometimes carrying resistance genes?
Transposon
What is the inducer of the LacI repressor? What does it do?
Allolactose, inactivates repressor for transcription to proceed
Which lipid carrier transports peptidoglycan precursor across the membrane during cell wall synthesis?
Bactoprenol
What is the stringent response pathway in relation to dormancy?
Decreased rRNA and tRNA synthesis for cells to become dormant (decreased DNA replication and cell division)
UV rays are a strong form of ________radiation that causes ______dimers.
Nonionizing, pyrimidine
What is the meaning of genetic drift?
Random process that can cause gene frequencies to change over time, evolution in the absence of natural selection